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Append Control Points

Summary

Combines control points to an existing control point table.

The points to be appended are the results from either the Compute Tie Points tool or the Compute Control Points tool, or a point feature class.

Usage

  • If both the Z Value Field Name and the Input DEM parameters are set, the Z Value Field Name takes priority. If neither the Z Value Field Name nor the Input DEM parameter is set, the z-value is set to 0 for all ground control points (GCP) and check points.

  • Use caution when invoking the Append Option — it is applicable only when the tie points in the input and target control point table have the same transformation.

Syntax

AppendControlPoints_management (in_master_control_points, in_input_control_points, {in_z_field}, {in_tag_field}, {in_dem}, {in_xy_accuracy}, {in_z_accuracy}, {Geoid}, {area_of_interest}, {append_option})
ParameterExplanationData Type
in_master_control_points

The input control point table. This is usually the output from the Compute Tie Points tool.

Feature Class; Feature Layer
in_input_control_points

A point feature class that stores control points. It could be the control point table created from the Compute Control Points tool, the Compute Tie Points tool, or a point feature class that has ground control points.

Feature Class; Feature Layer
in_z_field
(Optional)

The field that stores the control point z-values.

If both the Z Value Field Name and the Input DEM parameters are set, the Z value field is used. If neither the Z Value Field Name nor the Input DEM parameter is set, the z-value is set to 0 for all ground control points and check points.

Field
in_tag_field
(Optional)

A field in the input control point table that has a unique value. This field will be added to the target control point table, where the tag field can be used to bring in identifiers associated with ground control points.

Field
in_dem
(Optional)

A DEM to use to obtain the z-value for the control points in the input control point table.

If both the Z Value Field Name and Input DEM parameters are set, the Z value field is used. If neither the Z Value Field Name nor the Input DEM parameter is set, the z-value is set to 0 for all ground control points and check points.

Mosaic Dataset; Mosaic Layer; Raster Dataset; Raster Layer
in_xy_accuracy
(Optional)

The input accuracy for the X and Y coordinates. The accuracy is in the same units as the in_input_control_points.

This information should be provided by the data provider. If the accuracy information is not available, skip this optional parameter.

Double
in_z_accuracy
(Optional)

The input accuracy for the vertical coordinates. The accuracy is in the units of the in_input_control_points.

This information should be provided by the data provider. If the accuracy information is not available, skip this optional parameter.

Double
Geoid
(Optional)

The geoid correction is required by rational polynomial coefficients (RPC) that reference ellipsoidal heights. Most elevation datasets are referenced to sea level orthometric heights, so this correction would be required in these cases to convert to ellipsoidal heights.

  • NONENo geoid correction is made. Use NONE only if your DEM is already expressed in ellipsoidal heights. This is the default.
  • GEOIDA geoid correction will be made to convert orthometric heights to ellipsoidal heights (based on EGM96 geoid).
Boolean
area_of_interest
(Optional)

Defines an area of interest extent by entering minimum and maximum x- and y-coordinates in the spatial reference of the input control point table.

Envelope; Feature Layer; Feature Class
append_option
(Optional)

Specifies how control points will be appended to the control point table.

  • ALLAdd all points in the input control point table to the target control point table, including GCPs, check points, and all tie points. This is the default.
  • GCPAdd only GCPs in the input point table to the target control point table.
  • GCPSETAdd GCPs and tie points specifically associated with the GCPs to the target control point table.Use caution with this option—it is applicable only when the tie points in the input and target control point table have the same transformation. The tie points might not be in the desired positions if they were computed using a different adjustment process.
String

Derived Output

NameExplanationData Type
out_master_control_points

The updated control points.

Feature Class; Feature Layer

Code sample

AppendControlPoints example 1 (Python window)

This is a Python sample for the AppendControlPoints tool.

#===========================
#AppendControlPoints
'''Usage: AppendControlPoints_management(in_master_control_points, 
{in_z_field}, {in_tag_field}, {in_dem}, {in_xy_accuracy}, 
{in_z_accuracy}, {Geoid}, {area_of_interest}, {append_option}
'''

import arcpy
arcpy.env.workspace = "C:/Workspace"

arcpy.management.AppendControlPoints("calval_allpoints_dem1", 
    "C:\test\calval_allpoints_dem1", "Score", "Ways", "calval",1, 2, "NONE", 
"-79.6407162269889 43.4853802421312 -79.094324938576 44.0836924137218", "GCP")
AppendControlPoints example 2 (stand-alone script)

This is a Python script sample for the AppendControlPoints tool.

#append control points

import arcpy
arcpy.env.workspace = "c:/workspace"

#append the control points and tie points
target = "BD.gdb/tiePoints"
in_controlPoints = "BD.gdb/controlPoints"
dem = "BD.gdb/dem"
AOI = "-79.6407162269889 43.4853802421312 -79.094324938576 44.0836924137218"
AppOpt = "GCP"


arcpy.AppendControlPoints_management(target, in_controlPoints, "", dem, "", "", "", AOI, appOpt)

Environments

This tool does not use any geoprocessing environments.

Licensing information

  • Basic: No
  • Standard: Yes
  • Advanced: Yes